Answer: 
Step-by-step explanation:
Given: A cubic kilometer=
cubic centimeters
The volume of world’s oceans=
cubic kilometers of water.
⇒ The volume of world’s oceans=
cubic centimeters of water.
Volume of a bucket = 20,000 cubic centimeters of water.
The number of bucket-loads would it take to bucket out the world’s oceans
![\Rightarrow\ n=\frac{1.4\times10^{9+15}}{0.2\times10^5}......[a^n\times a^m=a^{m+n}]\\\Rightarrow\ n=7\times10^{24-5}.....[\frac{a^m}{a^n}=a^{m-n}]\\\Rightyarrow\ n=7\times10^{19}](https://tex.z-dn.net/?f=%5CRightarrow%5C%20n%3D%5Cfrac%7B1.4%5Ctimes10%5E%7B9%2B15%7D%7D%7B0.2%5Ctimes10%5E5%7D......%5Ba%5En%5Ctimes%20a%5Em%3Da%5E%7Bm%2Bn%7D%5D%5C%5C%5CRightarrow%5C%20n%3D7%5Ctimes10%5E%7B24-5%7D.....%5B%5Cfrac%7Ba%5Em%7D%7Ba%5En%7D%3Da%5E%7Bm-n%7D%5D%5C%5C%5CRightyarrow%5C%20n%3D7%5Ctimes10%5E%7B19%7D)
hence, 
bucketloads would it take to bucket out the world’s oceans.
PEMDAS Solve the parentheses first so 9+4=13. Then do the division so 6/6=1. Now the equation is 37- 13+ 1. Then work left to right. 37-13= 24 then 24+1=25.
1)b
2)a
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